Wrist pin



,May 14, 1929. I c. J. MCDONNELL 1,712,527

WRIST PIN Original Filed April 25, 1927 I I 9 L1 L -J W. m flovwwwPatented May 14, 1929.

warren STATES PATENT OFFICE.

CLEMENT J. MGDONNELL, OF TITUSVILLE, PENNSYLVANIA.

WRIST PIN.

Application fi1ed April 25, 1927, Serial No. 186,344. Renewed October15, 1928.

This invention relates to wrist pins and, although this new pin may beused to advantage anywhere that such pins are requlred, it is especiallyuseful in pivotally connecting the crank to t 1e pitinan in theoperating mechanism used in the drilling and pumping of wells. lit isthe present practice in the art relating to the drilling and pumping ofwells, especially oil wells, to secure the wrist p n to the crank and tojournal the pi'tinan on said pin. The present wrist pins, alter a shorttime in operation, work loose in the cranks and enlarge the holesthrough which the wrist pins pass and, thus, the wrist pins becomelooser and looser. One of the principal olr 'jects of this invention isto make provision for lirinly anchoring the wrist pin to the crank sothat it will not work loose. It will be readily understood that workingloose of the wrist pin entails the installation of a new pin, and thatthe new pin must be made larger than the old one in order to tightly fitin the crank. It follows that the substituted pin must be of specialconstruction, thus entailing large expense.

Other objects and advantages will-appear in the subjoined detaileddescription.

The accompanying drawings illustrate the invention. l

Figure 1 is a longitudinal section of a. wrist pin constructed inaccordance with the pro visions oi this invention, fragments oi? a crankand pitiuan being indicated in broken lines. The locking lug on thewasher is shown n solid lines in position to lock the nut and is shownin broken lines in its original position, before bending.

liigureil an elevatioi'i from the left of Figure 1.

Figure Sis a longitudinal view of the pin body.

Figure i is a sectional view on the line 111- dicated by l-l, Figure 1.

lligure 5 is a sectional view similar to Figure 4; showing a n'iodiliedform of pin body.

The body oi the pin comprises portions having dil'lerent diameters, apitman pivoting portion 6, a crank engaging anchoring portion or stud 7,and an annular flange 8 interposed between the portions tl, 7. In thisinstance, the portion 6 is of slightly larger onaineter than theport-ion 7. The pltlnan, 1ndicated at A, is engaged by the body portion6 and the portion 7 passes through a hole 9 in the crank which isindicated at B. The

portion 7 is provided with screw threads 10 to hold a nut 11.

In this instance, a washer 12 is interposed between the crank and thenut 11 and said washer is held against turning relative to the stud 7 byreason of it bein provided with an inwardly projecting lug 13 whichprojects into a slot 1 1 extending longitudinally in the stud 7. The nut11 is locked against turning, after being screwed up tight, by alaterally projecting flange 141 on the *asher 12, said flange being bentoutwardly 'll'Olll the washer after the nut is .in position. When thewasher is n'lanutactured, the flange 14-1 is aligned with the body 01'the washer as unheated in broken lines in Figure 1.

Projecting from the flange 8 is a dowel or dowels 15 which project intoholes 16 in the crank. The dowels may be secured to the flange 8 in anysuitable manner and, in this instance, screw threaded into said flange.it will be seen that the dowels prevent turni of the flange 8, thuspreventing, or air .ng in preventing, the turning of the stud 7 in thecrank. In this instance, the stud *Z' in Figures 1 to l, is circular incross section and itinay also be advisable to provide further means forpreventing turning of the stud in the crank and such means may be, "forexample, a key 1'? fitting in a key seat 18 in the periphery oi the studT. he key Il'i' engage:.-; in a key seat 19 in the crank.

From the in. egoing it will. now appear that the inventioncomprises therelatively large. llayugo 8 with 'incans to secure said flange to thecrank. The flange 8 tends to prevent rocking o'li ..d in the crank andthe dowels a so aid in preventing such rocking, thus insuring againstthe hole 9 in the crank being increased in size. It is to be understoodthat either toe dowels or the key may be omitted, although it preferableto one ploy both.

The body portion (3 is provided with a radially extending oil duct or ducts 20 which communicate with an axial duct 21 which may be filled withlubricant through a valved nipple 22 that is screw threaded or otherwisesecured to the body portion (3, as indicated at 23.

Adjust-ably secured to the body .)ortion is a flanged collar 24., thepitnlan being interposed between the flange 8 and said collar 24:. Toa-djustably secure the collar 524i. in place, the body portion 6 isprovided with a pluill rality of seats 25 which may be selectivelyengaged by a set screw 26 that is screw threaded through the collar 24.The seats 25 are'positioned at intervals along the body portion 6.

To use the invention described above, the

pin body will be separated from the elements that secure it to the crankand pitma-n, and the stud? will be driven into the hole 9 provided forit in the crank and the studs will engage in the holes 16. Then thewasher 12 will be placed over the stud and the nut 11 screwed tightlyagainst said washer, and

then the flange 141 will be bent outwardly against the side of the nutas in solid lines in Figure 1. This firmly; secures the pin bodyto thecrank.

. The pit-man will then beslid onto the body portion 6, the collar 24'placed in position on the end portion of the pin body outside of thepit-man and the set screw 26 will be engaged with the appropriate seatso as to prevent the pitnian from sliding off of the pin body. Aquantity of lubricant will then be injected through the nipple 22 into 7reference characters with the addition of the letter a. It will be notedthat in Figure'5 the stud 7 instead of being of circular cross section,is rectangular in cross section and, accordingly, a key corresponding tothe key 17 is not necessary, and is omitted.

1 claim:

1. Awrist pin comprisinga body provided with a cranlnengaging portionand a pitinanengagingportion and a flange, between said portions, ameans fixed to the flange to secure the flange to the crank, a nutscrewed onto the crank-engagingportion, a collar on the.

pitman-engaging portion, and a means to hold the collar in place. i

2. A wrist pin comprising a body provided with a crank-engaging portionand a pitmanengaging portion and a flange between said portions, thecrank-engaging portion provided with a slot, a means fixed tothe flangeto' secure the flange to the crank, a nut screwed onto thecrank-engaging portion, a

collar on v the pitman-cngaging portion, a means to hold the collar inplace, and a washer between the nut and flange provided with an inwardlyprojecting lug projecting into the slot, said washer having a laterallyprojecting flange bent outwardly along the edge of the nut to preventunscrewing thereof.

3. A wrist pin comprising a body provided with av crank-engaging portionand a pitmanengaging portion and a flange between said portions, a.means fixed to the flange to secure the flange to the crank, a keymounted in the crank-nigaging portion to engage the crank, a nut screwedonto the crank-engaging portion, a collar on the pilman-engagingportion, and a means to hold the collar in place.

4:. A wrist pin comprising a body provided with a crank-engaging portionand a pitmanengaging portion and a flange between said portions, the eralz-cngaging portion provided with a slot, a key mounted in thecrankengaging portion to engage the crank, a nut screwed onto thecrank-engaging portion, a collar on the pitman-cngaging portion, a meansto hold the collar in place and a washer between the nut and fla'ngeprovided with an inwardly projecting lug projecting into the slot, saidwasher provided with a. laterally projecting flange bent outwardly alongthe edge of the nut. Y

A wrist pin comprising a body provided with a crank-engaging portion anda pitmanengaging portion and a flange between said portions, a nutscrewed onto the crank-engaging portion, a means to prevent turnin; ofthe crank-engaging portion in the crank, the crank-engaging portionprovided with a slot, a Washer between the nut and flange provided withan inwardly projecting lug engaging in the slot. the washer having alaterally projecting flange extending alum, the edge of the nut, acollar on the pitmanengaging portion, a means to hold the collar inplace, and a nipple screwed into one end of the body, said body providedwith a duct connnunicating with the nipple and provided with a lateralduct connected with the first duct and opening to the periphery of thepitman-engaging portion.

Signed at Los Angeles, this 18th day of April, 1927.

CLEMENT J. MoDONN ELL.

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